1. Field of the Invention
The present invention relates to a one-way clutch for use in an automobile, a motor-bicycle, or the like.
2. Description of the Prior Art
Conventionally, in the above kind of one-way clutch, cam members are held in place by a cage between an inner ring and an outer ring and urged in one direction by a spring, and end bearings are disposed on both sides of the cage between the inner ring and the outer ring. It is common to make such inner and outer rings of carbon steel. Conventionally, the inner and outer rings of carbon steel have been normally subjected to an induction hardening process or a carburizing process so that their peripheries (surface portions) are made harder than their internal portions.
When an excessive torque is transmitted from the inner ring to the outer ring, the outer ring is subject to strain, and called "roll-over" (a phenomenon in which the cam members decline too much over their engaging position and the inner ring idles) occurs, which has been a factor for limiting the maximum transmission torque of the one-way clutch.
A conventional solution to the roll-over is to increase the radial thickness of the outer ring and reduce the strain or deformation of the outer ring.
However, the scheme of increasing the radial thickness of the outer ring to prevent the roll-over increases the size and weight of the outer ring.